1. Technical Field
The disclosure relates to a method and an apparatus for broadcast assistance in a direct communication system.
2. Related Art
Advertising is an attractive revenue growing service for service providers. For example, Google Inc. earns significant revenues through its advertisement services. In a cellular network, advertisements may be implemented through a broadcast function in a communication system with broadcast channels and resource indications. A base station (BS) broadcasts the resource area map of the advertisement message and broadcasts the advertisement message at the allocated area. A mobile station (MS) listens to the map and prepares to listen to the advertisement message in the allocated resource. For example, in Long Term Evolution (LTE), the map might be the region for the Physical Control Channel (PDCCH), and in the IEEE 802.16e/802.16m standards, the map might be the region for the MAP/A-MAP/EMBS-MAP. The BS then broadcasts the advertisement message on the allocated area.
An advertisement scheme can also be implemented in a direct communication system, and a general procedure for advertising in a direction communication system for one to one communication may be as follows. A device contents the resource for transmission and an access point acknowledges the transmission. The device then transmits the data. In a broadcasting scenario, the procedure can be modified to suit the situation at hand.
An approach to realize broadcasting in the direct communication system is for the broadcast device to wait for a time window. If there is no device transmitting signals, the device broadcasts the message. This approach puts the broadcast function at a low priority, even though this approach is adopted for the IEEE 802.11 standard. However, performance cannot be guaranteed when there is a plurality of direct communication devices contenting for the available resource. In some cases, such as in the broadcast transmission for streaming or video applications, equal priority may be necessary.